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1.
Crit Rev Food Sci Nutr ; 60(4): 660-669, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-30596263

RESUMO

Vitamin D deficiency is considered a global public health problem with high prevalence in children and adolescents. The majority of the studies in the literature have identified a relationship between vitamin D insufficiency/deficiency and obesity, as well as other traditional cardiometabolic risk factors in children and adolescents. Scarce studies address vitamin D status with oxidative stress and inflammation in the young population. The aim of this systematic review was to evaluate the evidence of the association of vitamin D status with oxidative stress and inflammation in children and adolescents. This is a systematic review based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyzes (PRISMA) guideline on reporting systematic reviews. Eight studies were selected for this review. All included studies evaluated inflammatory biomarkers and two out of eight evaluated biomarkers of oxidative stress. The majority of the studies (five out of eight) found association of vitamin D status with biomarkers of oxidative stress and inflammation such as C-reactive protein (CRP), interleukin-6 (IL-6), cathepsin S, vascular cell adhesion molecule-1 (VCAM-1), malondialdehyde (MDA), myeloperoxidase, 3-nitrotyrosine, and superoxide dismutase (SOD). Vitamin D status is associated with oxidative stress and inflammation in the majority of the studies with children and adolescents. Thus, the assessment of vitamin D status is important because it is associated with nontraditional cardiometabolic markers in the pediatric population (review registration: PROSPERO CRD42018109307).


Assuntos
Inflamação/sangue , Inflamação/metabolismo , Estresse Oxidativo , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/metabolismo , Vitamina D/análise , Vitamina D/metabolismo , Adolescente , Biomarcadores/sangue , Biomarcadores/metabolismo , Criança , Humanos , Vitaminas/sangue , Vitaminas/metabolismo
2.
Brain Res ; 1727: 146550, 2020 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-31726043

RESUMO

The prion protein (PrPC) binds copper and affects copper metabolism, albeit among a poorly understood functional landscape. Much of the data on physiological roles of PrPC were obtained in mice of mixed genetic background deficient of the PrPC-coding gene Prnp. This strategy is currently under scrutiny due to the flanking gene problem, in particular related with a polymorphism, typical of both the 129Sv and 129Ola mouse substrains, in the Sirpa gene located in the vicinity of Prnp. Here we report an investigation of biochemical properties of Cu(I)-ATPases as a function of genotype in two strains of PrPC-deficient mice. We found that both the brain and liver of Prnp-null mice of mixed B6;129Sv background had diminished activity, accompanied by increased catalytic phosphorylation of Cu(I)-ATPase, as compared with the respective wild-type animals. However, no such differences were found between Prnp-null and wild-type mice of a B10;129Ola background. Activity of Cu(I)-ATPase was strongly reduced in brain tissue from mice of 129Sv strain, when compared with wild-type either of B6;129Sv, and especially of mice of the B6 strain. No differences between wild-type and Prnp-null brain tissue were noted in the expression of either Atp7a or b genes, and RFLP analysis indicated that the Sirpa129 polymorphism was present in both the B6;129Sv and B10;129Ola Prnp-null mouse colonies used in this study. The results suggest a novel substrain-dependent effect of 129Sv, but not 129Ola, genotype upon the regulation of the Cu(I)-ATPase catalytic cycle in Prnp-null mice, rather than either a Prnp-dependent, or a 129 strain-dependent effect.


Assuntos
Encéfalo/metabolismo , ATPases Transportadoras de Cobre/metabolismo , Proteínas Priônicas/metabolismo , Animais , Hipocampo/metabolismo , Fígado/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fosforilação , Proteínas Priônicas/genética , Especificidade da Espécie
4.
Ultrasound Obstet Gynecol ; 49(4): 533-539, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27063344

RESUMO

Aortopulmonary window is a rare congenital cardiac anomaly characterized by communication between the aorta and the pulmonary artery above the semilunar valves. Prenatal diagnosis is rare. We report four fetuses with aortopulmonary window and review the relevant literature. Approximately half of the reported cases had additional cardiac defects. None had chromosomal abnormalities. In cases with normal cardiac connections, the diagnosis can be made prenatally on the standard three-vessel view, as seen in two of our cases. In one fetus with complete transposition of the great arteries, the diagnosis was made retrospectively on sagittal views. In the remaining case, the window was seen postnatally but could not be identified retrospectively due to the abnormal superoinferior relationship of the ventricles and vessels. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.


Assuntos
Aorta Torácica/anormalidades , Ecocardiografia/métodos , Cardiopatias Congênitas/diagnóstico por imagem , Artéria Pulmonar/anormalidades , Adulto , Aorta Torácica/diagnóstico por imagem , Aorta Torácica/embriologia , Diagnóstico Precoce , Feminino , Humanos , Diagnóstico Pré-Natal/métodos , Estudos Prospectivos , Artéria Pulmonar/diagnóstico por imagem , Artéria Pulmonar/embriologia , Sensibilidade e Especificidade
6.
Rev. bras. plantas med ; 17(4): 604-613, out.-dez. 2015. tab, graf
Artigo em Português | LILACS | ID: lil-763223

RESUMO

RESUMORubiaceae é uma família botânica com grande potencial químico e biológico Neste trabalho realizou-se a prospecção fitoquímica e avaliou-se as atividades citotóxica, antioxidante e antifúngica dos extratos diclorometânicos e metanólicos das folhas de Duroia saccifera, Ferdinandusa goudotiana, F. hirsuta, F. paraensis, Ferdinandusa sp., Palicourea corymbifera e P. guianensis. A avaliação da citotoxicidade foi realizada empregando-se o ensaio de toxicidade sobre Artemia salina. A atividade antifúngica foi determinada pelo método de difusão em ágar utilizando-se os fungos: Epidermophyton floccosum, Microsporum canis 32905, M. gipseum 29/00, Trichophyton mentagrophytes ATCC 9533/03, T. rubrum ATCC 28189, T. tonsurans 21/97, Cladosporium cladosporioides, C. sphaerospermum, FusariumU. 662/06, Scytalidium U. 661/06, Candida albicans ATCC 3632 e C. albicans U. 5/99. A atividade antioxidante foi determinada através dos ensaios de redução do radical livre 1,1-difenil-2-picrilhidrazila (DPPH) e de descoloração do cátion radical ácido-6-sulfônico-2,2-azinobis-3-etilbenzotiazolina (ABTS). Para o ensaio de toxicidade sobre A. salina observou-se maior toxicidade no extrato metanólico de F. goudotiana, que se mostrou tóxico até a concentração de 5 µg mL-1. A presença de princípios antifúngicos foi observada em F. hirsuta e F. paraensiscontra quatro dos fungos testados. Na avaliação da atividade antioxidante os extratos metanólicos mostraram maior atividade que os extratos diclorometânicos, sendo coincidente o resultado obtido através de ambos os métodos (redução do DPPH e descoloração do ABTS). Os resultados criam possibilidades para futuras investigações relacionadas à estrutura e atividade dos componentes de cada extrato ativo.


ABSTRACTRubiaceae is a plant family with great chemical and biological potential. In this work a phytochemical prospection was performed and it was assessed the cytotoxic, antioxidant and antifungal activities of dichloromethanic and methanolic extracts of the leaves of Duroia saccifera, Ferdinandusagoudotiana, F. hirsuta, F. paraensis, Ferdinandusa sp., Palicourea corymbifera and P. guianensis. The cytotoxicity evaluation was carried out using the test toxicity on Artemia salina. The antifungal activity was determined by agar diffusion method using fungi: Epidermophyton floccosum, Microsporum canis 32905, M. gipseum 29/00, Trichophyton mentagrophytes ATCC 9533/03, T.rubrum ATCC 28189, T. tonsurans 21/97 , Cladosporium cladosporioides, C. sphaerospermum, FusariumU. 662/06, Scytalidium U. 661/06, Candida albicans ATCC 3632 and C. albicans U. 5/99. The antioxidant activity was determined by testing the amount of free radical 1,1-diphenyl-2-picrylhydrazyl (DPPH) and the discoloration of the radical cation 6-sulfonic acid-2 ,2-azinobis-3-ethylbenzothiazoline (ABTS). For the toxicity test on A. salina greater toxicity in the methanol extract of F. goudotiana was observed, which proved to be toxic up to a concentration of 5 µg mL-1. The presence of antifungal principles was observed in the F. hirsuta and F. paraensis against four tested fungi. In the evaluation of the antioxidant activity, the methanol extracts showed greater activity than the dichloromethanic ones, being similar the obtained result through both methods (reduction of DDPH and ABTS decolorization) . The results create possibilities for future researches related to the structure and activity of the components of each active extract.


Assuntos
Plantas Medicinais/classificação , Ecossistema Amazônico/classificação , Rubiaceae/metabolismo , Artemia/anatomia & histologia , Rubiaceae/classificação , Citotoxinas , Antifúngicos/farmacologia , Antioxidantes/farmacologia
7.
Braz J Biol ; 74(2): 290-301, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-25166313

RESUMO

The aim of this study was to analyse the composition, structure and spatial and temporal patterns of diversity and abundance of the ichthyofauna of the Santa Cruz Reservoir in semi-arid Brazil. Data were collected quarterly at eight sampling locations on the reservoir between February 2010 and November 2011 using gillnets from 12- to 70-mm mesh that were left in the water for 12h00min during the night. We evaluated the composition, structure and assemblage descriptors (Shannon-Wiener diversity index and equitability, respectively) and catch per unit effort by the number (CPUEn) and biomass (CPUEb) of the ichthyofauna. The 6,047 individuals (399,211.6 g) captured represented three orders, ten families and 20 species, of which four belonged to introduced species. The family Characidae was the most abundant with a total of 2,772 (45.8%) individuals captured. The species-abundance curve fit the log-normal model. In the spatial analysis of diversity, there were significant differences between sampling sites in the lacustrine and fluvial regions, and the highest values were found in the lacustrine region. In the temporal analysis of diversity, significant differences were also observed between the rainy and dry seasons, and the higher values were found during the dry season. Equitability followed the same spatiotemporal pattern as diversity. The Spearman correlation was significantly negative between diversity and rainfall. A cluster analysis spatially separated the ichthyofauna into two groups: one group formed by sampling sites in the fluvial region and another group formed by the remainder of the points in the lacustrine region. Both the CPUEn and CPUEb values were higher at point 8 (fluvial region) and during the rainy season. A two-way ANOVA showed that the CPUEn and CPUEb values were spatially and temporally significant. We conclude that the spatial and temporal trends of diversity in the Santa Cruz reservoir differ from those of other Brazilian reservoirs but that the fish community composition and spatiotemporal patterns of abundance were similar.


Assuntos
Biodiversidade , Peixes/classificação , Animais , Brasil , Água Doce , Densidade Demográfica , Estações do Ano
8.
J Obstet Gynaecol ; 32(1): 45-9, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22185536

RESUMO

This study aimed to assess outcomes of expectant management for early preterm premature rupture of membranes (PPROM). This retrospective cohort involved 66 women with PPROM <28 weeks managed in a single hospital (1999-2006). Main outcomes were chorioamnionitis, severe maternal morbidity (maternal sepsis, haemorrhage/blood transfusion, hysterectomy or admission to intensive care unit), maternal mortality, low birth weight, preterm birth, neonatal infection and perinatal mortality. Mean gestational ages at PPROM and delivery were 21.7 ± 4.2 and 28.4 ± 5.9 weeks, respectively. Chorioamnionitis was diagnosed in 47%; no cases of severe maternal morbidity or mortality occurred. Stillbirth rate was 25.7% and >80% of infants were delivered before 34 weeks. Neonatal infection was diagnosed in 42.9% of the 49 live-births. Overall survival rate was 57.6%. Expectant management of PPROM <28 weeks resulted in high rates of chorioamnionitis and preterm deliveries but in over half of the cases, a live infant was discharged home.


Assuntos
Países em Desenvolvimento , Ruptura Prematura de Membranas Fetais/epidemiologia , Resultado da Gravidez , Adulto , Brasil/epidemiologia , Feminino , Humanos , Gravidez , Estudos Retrospectivos
9.
Arch Biochem Biophys ; 513(2): 126-30, 2011 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-21784058

RESUMO

There is some evidence to show a possible role of guanosine in the modulation of cellular function, in particular, in the neuronal system. However, nothing is known about the role of guanine in renal function. The aim of the present work was to investigate the role of guanine on modulation of Na+-ATPase activity in isolated basolateral membrane (BLM) of the renal cortex. Guanine inhibited the enzyme activity in a dose-dependent manner with maximal effect (56%) obtained at 10⁻6 M. This effect was reversed by DPCPX (8-cyclopentyl-1,3-dipropylxanthine), an antagonist of A1 receptors, but it was not changed by 10⁻8 M DMPX (3,7-dimethyl-1-propargylxanthine) or 10⁻8 M MRS (2,3-diethyl-4,5-dipropyl-6-phenylpyridine-3-thiocarboxylate-5-carboxylate), antagonists of A2 and A3 receptors, respectively. Furthermore, it was observed that guanine increased [γ-³5S]GTP-specific binding with the maximal effect observed at 10⁻6 M and this effect was abolished by 10⁻6 M GDPßS. The inhibitory effect of 10⁻6 M guanine on Na+-ATPase activity was reversed by 10⁻6 M GDPßS, 10⁻6 M forskolin, 10⁻6 M pertussis toxin and 10⁻8 M cholera toxin. These results indicate that guanine binds to a DPCPX-sensitive receptor promoting the activation of Gi protein and leading to a decrease in cAMP level and, consequently, inhibition of BLM Na+-ATPase activity.


Assuntos
Adenosina Trifosfatases/antagonistas & inibidores , Proteínas de Transporte de Cátions/antagonistas & inibidores , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/metabolismo , Guanina/farmacologia , Córtex Renal/metabolismo , Antagonistas do Receptor A1 de Adenosina/farmacologia , Adenosina Trifosfatases/química , Adenosina Trifosfatases/metabolismo , Animais , Proteínas de Transporte de Cátions/química , Proteínas de Transporte de Cátions/metabolismo , Membrana Celular/metabolismo , AMP Cíclico/metabolismo , Inibidores Enzimáticos/farmacologia , Guanina/metabolismo , Técnicas In Vitro , Córtex Renal/efeitos dos fármacos , Túbulos Renais Proximais/efeitos dos fármacos , Túbulos Renais Proximais/metabolismo , Cinética , Suínos , Xantinas/farmacologia
10.
Int J Sports Med ; 31(11): 784-9, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20812165

RESUMO

The purpose of this work was to apply a simple method for acquisition of power output (PO) during the Wingate Anaerobic Test (WAnT) at a high sampling rate ( S(R)) and to compare the effect of lower S(R) on the measurements extracted from the PO. 26 male subjects underwent 2 WAnTs on a cycle ergometer. The reference PO was calculated at 30 Hz as a function of the linear velocity, the moment of inertia and the frictional load. The PO was sampled at 0.2, 0.5, 1, 2 and 5 Hz. Both the peak (16.03±2.22 W·kg (-1)) and mean PO (10.34±1.01 W·kg (-1)) presented lower relative values when the S(R) was lower. Peak PO was attenuated by 0.29-42.07% for decreasing sampling rates, resulting in different values for 0.2 and 1 Hz ( P<0.001). When the S(R) was 0.2 Hz, the time to peak was delayed by 53.81% ( P<0.001) and the fatigue index was attenuated by 22.12% ( P<0.001). In conclusion, due to the differences achieved here and the fact that the peak flywheel frequency is around 2.3 Hz, we strongly recommend that the PO be sampled at 5 Hz instead of 0.2 Hz in order to avoid biased errors and misunderstandings of the WAnT results.


Assuntos
Limiar Anaeróbio , Desempenho Atlético/fisiologia , Teste de Esforço/métodos , Adolescente , Adulto , Ergometria , Humanos , Masculino , Adulto Jovem
11.
J Sports Med Phys Fitness ; 50(2): 126-31, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20585290

RESUMO

AIM: Little is known about the physiological response during slideboard exercise (SE). The aim of the present study was to analyse the oxygen uptake (V.O2), the heart rate (HR) and the energy expenditure (EE) during a typical slideboard exercise session and investigate differences on these variables when performing the same choreography at two different cadences (130 e 145 beats per minute - bpm). METHODS: The sample comprised 13 female university students (21,77+/-0,97 years), apparently healthy and physically active, with past training in SE and mastering the technical levels 1 and 2. The subjects performed randomly exercise sessions at 130 bpm and 145 bpm. The ventilatory response was measured by an open air circuit system (COSMED K4b2, Rome, Italy) and HR was measured by a portable monitor (Polar Wireless Double Electrode, Kempele, Finland). HR and V.O2, during SE at 130 bpm, were 179.88+/-834 bpm and 37.95+/-3.71 mL/kg/min respectively. At 145 bpm SE mean values were 182.08+/-9.58 bpm and 39.67+/-3.82 mL/kg/min respectively. EE during 130 bpm exercise was 10.60+/-1.69 kcal/min and at 145 bpm was 10.90+/-1.36 kcal/min. No differences were found between 130 and 145 bpm in none of the variables. We conclude that slideboard exercise cardio respiratory response does not seem affected by the rhythm of execution. Moreover the EE associated with this type of exercise is above the literature reports for other types of group aerobic exercises.


Assuntos
Metabolismo Energético/fisiologia , Exercício Físico/fisiologia , Frequência Cardíaca/fisiologia , Consumo de Oxigênio/fisiologia , Feminino , Humanos , Adulto Jovem
12.
Arch Biochem Biophys ; 467(2): 261-7, 2007 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-17892855

RESUMO

In the present work, we demonstrate that adenine reduced Na(+)-ATPase activity in isolated basolateral membrane (BLM) of proximal tubule in a dose-dependent manner. Adenine metabolism was ruled out by TLC analysis of the potential [(3)H]adenine derived-metabolites. Specific binding of [(3)H]adenine to isolated BLM was observed in a dose-dependent manner with K(d) and B(max) of 242.6+/-27.6 nM and 2749.9+/-104.9 fmolmg(-1), respectively. Adenine increased the [(35)S]GTPgammaS specific binding and it was completely abolished by 10(-6)M GDPbetaS (G protein inhibitor) but it was not modified by DPCPX, DMPX and MRS1523, selective antagonists for A(1), A(2) and A(3) receptors, respectively. Furthermore, the inhibitory effect of adenine on the Na(+)-ATPase activity was blocked by 10(-6)M GDPbetaS, 1 microg/ml pertussis toxin (Gi protein inhibitor), 10(-6)M foskolin (adenylyl cyclase activator) and 10(-8)M cAMP. These data demonstrate that adenine inhibits the proximal tubule Na(+)-ATPase activity through the Gi protein-coupled receptor.


Assuntos
Adenina/administração & dosagem , Adenosina Trifosfatases/antagonistas & inibidores , Adenosina Trifosfatases/metabolismo , Proteínas de Transporte de Cátions/antagonistas & inibidores , Proteínas de Transporte de Cátions/metabolismo , Membrana Celular/metabolismo , Túbulos Renais Proximais/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Animais , Membrana Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Túbulos Renais Proximais/efeitos dos fármacos , ATPase Trocadora de Sódio-Potássio , Suínos
13.
Arq. bras. med. vet. zootec ; 58(6): 1229-1231, dez. 2006. ilus
Artigo em Inglês | LILACS | ID: lil-455073

RESUMO

Relata-se a ocorrência de metacercárias de Diplostomum compactum (Trematoda: Diplostomidae) infectando Geophagus brasiliensis (Teleostei: Cichlidae) do reservatório de Barra Bonita, rio Tietê, estado de São Paulo, Brasil. As metacercárias foram coletadas no globo ocular, fixadas em solução de AFA e coradas com carmim. As análises morfológicas e morfométricas de cinco espécimes foram realizadas por meio do sistema computadorizado de analise de imagem. Este foi o primeiro registro da ocorrência desse parasito no reservatório de Barra Bonita e também o primeiro registro em acará Geophagus brasiliensis.


Assuntos
Epidemiologia , Perciformes/anatomia & histologia , Processamento de Imagem Assistida por Computador/métodos , Trematódeos/isolamento & purificação
14.
Braz. j. biol ; 62(3)Aug. 2002.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1467642

RESUMO

Both the presence of receptors for gonadal steroids in the pineal gland and in vitro observations of direct action of melatonin upon Leydig cells, inhibiting testosterone secretion, indicate a direct connection between pineal gland and gonadal function. In the present study, we used a transmission electron microscope to analyze the morphologic parameters of Leydig cells from adult Swiss outbred white mice treated with daily subcutaneous injections of 100 µg of melatonin (N-acetyl, 5-methoxytryptamine), during 22 consecutive days, compared with sham-control animals which had only received the melatonin vehicle. The melatonin group of mice showed a decrease in nuclear volume and fractional nuclear volume; smooth and rough endoplasmic reticulum; mitochondria; and Golgi complex. Our data also showed an increase in cytoplasmic volume, fractional cytoplasmic volume, and lysosomes in these same animals. The results suggest that melatonin, directly or indirectly, alters the ultrastructure of mouse Leydig cells and possibly influences their secretory activity by inhibiting their capacity to secrete steroids.


No presente trabalho, utilizamos a microscopia eletrônica de transmissão para analisar os parâmetros morfológicos das células de Leydig de camundongos adultos, suíços outbred, tratados com uma injeção subcutânea diária de 100 µg de melatonina (5-metoxi-N-acetil-triptamina), durante 22 dias consecutivos, comparando-os com animais sham-controle que receberam apenas o veículo da melatonina. Os animais tratados com melatonina mostraram diminuição do volume nuclear, da fração volumétrica do núcleo, do retículo endoplasmático liso e rugoso, das mitocôndrias e do complexo de Golgi. Nos mesmos animais ocorreu, também, aumento do volume do citoplasma e da fração volumétrica do citoplasma e dos lisossomos. Esses resultados sugerem que a melatonina pode alterar, direta ou indiretamente, a ultra-estrutura das células de Leydig do camundongo, inibindo sua atividade de síntese, como a produção de esteróides.

15.
Braz. j. biol ; 62(3): 517-523, Aug. 2002. ilus, tab
Artigo em Inglês | LILACS | ID: lil-326225

RESUMO

Both the presence of receptors for gonadal steroids in the pineal gland and in vitro observations of direct action of melatonin upon Leydig cells, inhibiting testosterone secretion, indicate a direct connection between pineal gland and gonadal function. In the present study, we used a transmission electron microscope to analyze the morphologic parameters of Leydig cells from adult Swiss outbred white mice treated with daily subcutaneous injections of 100 µg of melatonin (N-acetyl, 5-methoxytryptamine), during 22 consecutive days, compared with sham-control animals which had only received the melatonin vehicle. The melatonin group of mice showed a decrease in nuclear volume and fractional nuclear volume; smooth and rough endoplasmic reticulum; mitochondria; and Golgi complex. Our data also showed an increase in cytoplasmic volume, fractional cytoplasmic volume, and lysosomes in these same animals. The results suggest that melatonin, directly or indirectly, alters the ultrastructure of mouse Leydig cells and possibly influences their secretory activity by inhibiting their capacity to secrete steroids


Assuntos
Animais , Masculino , Camundongos , Células Intersticiais do Testículo , Melatonina , Análise de Variância , Estudo de Avaliação , Células Intersticiais do Testículo
16.
Braz J Biol ; 62(3): 517-23, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12530190

RESUMO

Both the presence of receptors for gonadal steroids in the pineal gland and in vitro observations of direct action of melatonin upon Leydig cells, inhibiting testosterone secretion, indicate a direct connection between pineal gland and gonadal function. In the present study, we used a transmission electron microscope to analyze the morphologic parameters of Leydig cells from adult Swiss outbred white mice treated with daily subcutaneous injections of 100 micrograms of melatonin (N-acetyl, 5-methoxytryptamine), during 22 consecutive days, compared with sham-control animals which had only received the melatonin vehicle. The melatonin group of mice showed a decrease in nuclear volume and fractional nuclear volume; smooth and rough endoplasmic reticulum; mitochondria; and Golgi complex. Our data also showed an increase in cytoplasmic volume, fractional cytoplasmic volume, and lysosomes in these same animals. The results suggest that melatonin, directly or indirectly, alters the ultrastructure of mouse Leydig cells and possibly influences their secretory activity by inhibiting their capacity to secrete steroids.


Assuntos
Células Intersticiais do Testículo/efeitos dos fármacos , Melatonina/farmacologia , Análise de Variância , Animais , Células Intersticiais do Testículo/metabolismo , Células Intersticiais do Testículo/ultraestrutura , Masculino , Camundongos
17.
Braz. j. biol ; 61(4): 679-684, Nov. 2001. ilus, tab
Artigo em Inglês | LILACS | ID: lil-308298

RESUMO

In order to evaluate melatonin implication in the regulating of its own secretory process by pinealocytes, we used morphometric techniques for transmission electron microscopy. In mice treated with 100 mg of melatonin (N-acetyl-5-methoxy-tryptamine) by daily subcutaneous injection, we observed a decrease in number and volumetric density of lysosomes. Our results showed that melatonin influences the secretory activity of pinealocytes and participates in a complex secretory regulating mechanism


Assuntos
Animais , Masculino , Camundongos , Melatonina , Glândula Pineal , Complexo de Golgi , Lisossomos , Melatonina , Glândula Pineal
18.
Braz. j. biol ; 61(4)Nov. 2001.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1467573

RESUMO

In order to evaluate melatonin implication in the regulating of its own secretory process by pinealocytes, we used morphometric techniques for transmission electron microscopy. In mice treated with 100 mg of melatonin (N-acetyl-5-methoxy-tryptamine) by daily subcutaneous injection, we observed a decrease in number and volumetric density of lysosomes. Our results showed that melatonin influences the secretory activity of pinealocytes and participates in a complex secretory regulating mechanism.


A fim de avaliar a implicação da melatonina no controle de sua própria secreção pelos pinealócitos, utilizamos técnicas morfométricas aplicadas à microscopia eletrônica de transmissão. Em camundongos tratados com doses subcutâneas diárias de 100 mg de melatonina (5-metoxi-N-acetil-triptamina) observamos uma diminuição do número e da densidade volumétrica dos lisosomos nos pinealócitos. Esses resultados mostram que a melatonina atua sobre a própria glândula pineal, participando de um complexo mecanismo regulador da secreção nos pinealócitos.

19.
Braz J Biol ; 61(4): 679-84, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12071325

RESUMO

In order to evaluate melatonin implication in the regulating of its own secretory process by pinealocytes, we used morphometric techniques for transmission electron microscopy. In mice treated with 100 mg of melatonin (N-acetyl-5-methoxy-tryptamine) by daily subcutaneous injection, we observed a decrease in number and volumetric density of lysosomes. Our results showed that melatonin influences the secretory activity of pinealocytes and participates in a complex secretory regulating mechanism.


Assuntos
Melatonina/farmacologia , Glândula Pineal/efeitos dos fármacos , Animais , Complexo de Golgi/efeitos dos fármacos , Lisossomos/efeitos dos fármacos , Masculino , Melatonina/biossíntese , Camundongos , Glândula Pineal/metabolismo , Glândula Pineal/ultraestrutura
20.
Tissue Cell ; 31(2): 233-9, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10445300

RESUMO

In order to determine the effects of testosterone upon the function of the pineal gland we quantitated, under the electron microscope, the number of dense-core vesicles, lysosomes, lipid droplets and the fractional volume of the pineal gland components in adult male mice. We studied six groups of mice submitted to different treatments as follows: treated with testosterone propionate (0.1 mg/10 g body weight for 15 consecutive days), castrated and the respective control mice. In mice treated with testosterone we observed a decrease in the number and fractional volume of dense-core vesicles and an increase in the fractional volume of lysosomes and lipid droplets. In castrated mice, without treatment, we observed a decrease in the number of lysosomes and an increase in the number and fractional volume of dense-core vesicles. These results show that testosterone is closely related to the secretory process of mice pinealocytes, playing an inhibitory role upon the functional activity of the pineal gland.


Assuntos
Glândula Pineal/citologia , Testosterona/fisiologia , Animais , Masculino , Camundongos , Glândula Pineal/efeitos dos fármacos , Glândula Pineal/ultraestrutura , Testosterona/farmacologia
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